Tools such as taxation, regulation and legislation should be used to help curb the obesity epidemic, Green Party health spokesman Kevin Hague says.

Hague was speaking in New Plymouth last night. Earlier he told the Taranaki Daily News the same tactics used to fight smoking should be used against type-2 diabetes.

"If we look at what has worked in tobacco control it's taxation on tobacco products driving the price up, which drives consumption down," he said.

And there was regulation and legislation around displaying cigarettes and smoke-free environments, so the same tools that have seen such great gains on tobacco-related disease are the ones that the National Government refuses to use on obesity related disease, he said.

"We spend $500 million on treatment [for diabetes] a year. By 2021 that is going to be $2 billion or more, which will be 16 per cent of the health budget. And the rates of people getting type-2 diabetes are rising extremely steeply. So it's now one person in four above the age of 15 that had type-2 diabetes or has pre-diabetes, which is a metabolic condition just prior to diagnoses."

But this government had reduced the investment in diabetes prevention and continued to sit on its hands in relation to using taxation, legislation and regulation to make change around price availability and marketing of foods and drinks that are driving the obesity epidemic, Hague said.

There should some sort of levy put on sugary drinks and other foods as well as legislation to stop junk food and drink manufacturers marketing their products to children.

"National says that's a nanny state and we're a hands off government, we're just leaving it to individuals to make better choices.

"Well there is no evidence to support an individual approach and considerable evidence to support the approach I'm talking about. We are out of time to debate this, we need to be acting now."